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Trimethylamine N-oxide (TMAO) and phenylacetylglutamine (PAGln) are associated with acute myocardial infarction (AMI) and type 2 diabetes mellitus (T2DM). This study developed and validated a simple method firstly for simultaneously quantifying serum TMAO and PAGln using liquid chromatography-tandem mass spectrometry (LC-MS/MS).Serum samples from patients with T2DM, AMI, and healthy subjects were analyzed using a new LC-MS/MS method to evaluate TMAO and PAGln levels. Statistical analyses were performed to evaluate TMAO and PAGln distributions among different groups.Retention and separation of the two metabolites were achieved within 5 min. For both analytes, the assay was linear in a 0.02-10 µg/mL range, with 0.99 average linear correlation coefficients, and quantification limit values of approximately 0.010 µg/mL. The average recoveries of TMAO and PAGln were 96.3 % and 96.4 %, respectively. The intra-run and total coefficient variations were 3.5-4.8 % and 3.9-5.7 % respectively for TMAO; and 4.0-5.1 % and 4.6-6.3 % respectively for PAGln. TMAO and PAGln showed a moderate correlation (P 0.001) and their levels in patients with T2DM were significantly higher than those in healthy individuals (P 0.001). TMAO levels were higher in patients with T2DM than in patients with AMI (P 0.01). Patients with AMI had higher PAGln levels than healthy individuals (P 0.05). After adjusting for sex and age, the top tertile of PAGln was positively correlated with T2DM and AMI while that of TMAO was positively correlated with T2DM.Overall, a robust isotope dilution LC-MS/MS method was established, which may be beneficial for assessing the association between two metabolites with AMI and T2DM.

Objectives Measurement of the serum levels of vitamin B12 (VB12) is key for evaluating VB12 deficiency-dependent anemia. Immunoassay, the major method for determining VB12, tends to give false-normal results because of the presence of anti-intrinsic factor (IF-Ab) or other factors such as heterophilic antibodies et al. This study aimed to develop a liquid chromatography tandem mass spectrometry (LC-MS/MS) method that is helpful for distinguish false normal VB12 results measured by the immunoassay. Methods Different forms of VB12 were derivatized into CN-B12, which was collected through solid-phase extraction and analyzed via LC-MS/MS. 236 serum samples were measured both by LC-MS/MS and immunoassay, results were compared, and the IF-Ab effect was evaluated. Results The LC-MS/MS assay afforded a linear slope from 20 to 4,000 pmol/L for CN-B12. OH-VB12, methyl-VB12, and CoA-VB12 showed recovery within 89.3–109.5%. The intra-assay CV of VB12 was 2.6–4.1%, whereas the total CV was 9.3–9.8%. Passing–Bablok regression between LC-MS/MS and immunoassay results showed that the slope was 1.085 and the intercept was −15.691. The Bland–Altman plot showed that the mean difference and difference% were −34.6 pmol/L and 0.3%, respectively. Inter-rater agreement analysis showed that the linear weighted kappa value was 0.885, implying good agreement between the two methods. However, two samples were falsely elevated and one sample was falsely normal in the immunoassay compared with LC-MS/MS. The LC-MS/MS method helped in the distinction of false-normal VB12 results shown by the immunoassay. Conclusions The VB12 LC-MS/MS method can be used as an arbiter of clinically discordant immunoassay results.

To establish and validate a robust LC-MS/MS method for simultaneously measuring 8-oxoGuo, 8-oxodG, and NMN in serum and urine to evaluate the oxidative stress status.A Waters TQ-XS triple quadrupole mass spectrometer system coupled with an Acquity UPLC Primer HSS T3 column was chosen. The clinical performance was verified according to the CLSI C62-A and EP-15 guidelines. Furthermore, matched serum and urine samples from 22 apparently healthy check-ups, 20 patients with atherosclerosis, and 18 individuals with dementia were evaluated.The recovery for serum 8-oxoGuo, urine 8-oxoGuo, serum 8-oxodG, urine 8-oxodG, serum NMN, and urine NMN was 88.8-112.4%, 102.4-114.1%, 88.5-107.7%, 94.9-102.6%, 98.4-108.9%, and 88.5-108.6%, respectively. Based on the inter-assay results, total coefficient of variation, matrix effect, and carryover, the LC-MS/MS method was deemed robust. The limit of quantification was 0.017, 0.018, and 0.150 nmol/L for 8-oxoGuo, 8-oxodG, and NMN, respectively, which are suitable for accurate measurements in human serum and urine samples. Higher 8-oxoGuo and 8-oxodG levels and lower NMN levels, indicative of significantly higher oxidative stress status, were found in patients with dementia compared to healthy subjects.We established and validated a robust LC-MS/MS method to simultaneously measure 8-oxoGuo, 8-oxodG, and NMN in serum and urine.

The atherosclerotic coronary artery disease (CAD) risk assessment based on conventional risk factors have only moderate performance, and residual risks still exist. Thus, we reported here a cohort study that aims to identify and validate the new biosignatures (especially the metabolomics, lifestyle biomarkers and biological age), and elucidate their predictive effect on CAD and subsequent cardiovascular events.This prospective, single-center, cohort study commenced in March 2017 and seeks to examine patients undergoing coronary angiography (CAG) at the Beijing Hospital. Patients' baseline demographic and medical history data are captured by questionnaires. Blood samples are taken before CAG for clinical laboratory tests and metabolomics analyses. Traditional CAD risk factors are analyzed by routine assays. CAD-related metabolites from different metabolic pathways and lifestyle biomarkers are measured by liquid chromatography-tandem mass spectrometry methods. Biological ages are calculated based on the laboratory and metabolomics data. The enrolled patients attend annual follow-up examinations for 10 years. The primary end points are the composite end points of major adverse cardiovascular events, including death from any cause, non-fatal myocardial infarction, and non-fatal stroke. Quality management and control are carried out through the entire research process, including standardized baseline and follow-up investigation, intra- and inter-run quality controls for laboratory measurements, etc.Baseline data of the enrolled 2,970 patients from 2017 to 2020 were collected and are presented in this article. Among them, there were more males (62.5%) than females, and the patients tended to be old and overweight. The percentages of diagnosed hypertension and diabetes were 67.3% and 35.2%, respectively. A total of 8.5% had a family history of premature CAD. Their lipid profiles were within the normal range, probably due to the use of statins.This study has successfully initiated an investigation into the roles of new biosignatures in predicting CAD among Chinese Han patients undergoing CAG. To the best of our knowledge, this cohort is the first study systematically focusing on the association of lifestyle biomarkers and biological age with CAD risk. Findings from this study will provide biomarkers to discriminate the presence of CAD and to predict subsequent cardiovascular events.

Vitamin B12 (VB12) deficiency may lead to hyperhomocysteinemia and methylmalonic acidemia development which are risk factors of cardiovascular disease and nervous system impairment, respectively. However, few analytical methods are available to simultaneously quantify total homocysteine (tHcy) and methylmalonic acid (MMA) due to complex analytical requirements, such as sensitivity at nanomolar concentration, separation performance for succinic acid (SA), an endogenous isomer of MMA, and retention properties for polar compounds. Therefore, we developed and validated a simple and accurate liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of tHcy and MMA with the efficient separation of SA in human serum and urine. The clinical performance of the assay was validated according to CLSI C62-A guidelines. The recovery for serum tHcy was 95.2-105.8%, urine tHcy was 98.1-111.5%, serum MMA was 94.6-99.4%, and urine MMA was 101.6-105.6%. In addition, the LC-MS/MS method was found to be reliable based on the value of inter-assay imprecision and total imprecision coefficient variation (CV), matrix effect, and carryover. Standards and samples were stable in -20 °C for at least 2 months. The limits of quantifications (LOQs) were 0.074 nmol/mL for tHcy and 0.040 nmol/mL for MMA, which are suitable for detecting tHcy and MMA concentrations in human serum and urine. The concentration of tHcy and MMA in samples collected from 148 subjects were measured using this method. The results suggested that the concentrations of serum tHcy and MMA considerably differed between VB12 sufficient and deficient groups. Serum tHcy and serum MMA concentrations were inversely correlated with VB12 status. Our method represents a rapid technique for estimating tHcy and MMA concentrations in serum and urine samples without the need for derivatization and may be used to assess VB12 status in clinical applications.

Several amino acids, nucleotide metabolites, organic acids, and choline-related metabolites have been identified as possible risk factors for cardiovascular disease (CVD). However, a method that allows rapid processing of a large number of samples while simultaneously quantifying metabolite concentrations is currently unavailable. Here, we developed a simple and reliable method for quantifying metabolomic risk factors of CVD using liquid chromatography–tandem mass spectrometry (LC–MS/MS), and assessed its efficacy using serum samples from patients with angiographically defined coronary artery disease (CAD). Serum samples were mixed with isotopically labeled internal standards, extracted with methanol, and separated by hydrophilic interaction LC. MS detection was simultaneously performed in both positive and negative ionization modes coupled with real-time polarity switching, resulting in markedly improved monitoring capacity and reduced overall run time. In total, 20 metabolites were analyzed in 4 min. The mean linear correlation coefficients were higher than 0.999, with average analytical recoveries of 101.9% (range: 90.1–110.9%). The intra-run and total coefficients of variation (CV) were 1.02–6.11% and 1.25–9.41%, respectively. Several metabolites were significantly associated with traditional CVD risk factors. Multivariable logistic regression analysis revealed that tryptophan and hypoxanthine were negatively correlated with CAD, while trimethylamine-N-oxide was positively correlated with CAD. The method developed in this study is simple, precise, accurate, and provides a potentially convenient tool for CVD risk assessment and future research.

Background Several studies have identified a negative association between serum glycine (Gly) levels and metabolic syndrome (MetS). However, this association has not been fully established in the elderly. Methods A total of 472 Chinese individuals (272 males and 200 females, 70.1 ± 6.6 years old) participated in a population-based, cross-sectional survey in Beijing Hospital. The MetS and its components were defined based on the 2006 International Diabetes Federation (IDF) standard for Asians. Serum Gly concentration was determined using isotope dilution liquid chromatography tandem mass spectrometry. Result The proportion of patients with MetS decreased gradually with increasing Gly levels (p for trend

Background Alcoholic liver disease is commonly associated with intestinal barrier dysfunction. Alcohol-induced dysregulation of intestinal tight junction proteins, such as Zonula Occludens-1 (ZO-1), plays an important role in alcohol-induced gut leakiness. However, the mechanism of alcohol-induced disruption of tight junction proteins is not well established. The goal of this study was to elucidate this mechanism by studying the role of microRNA 212 (miR-212) and inducible nitric oxide synthase (iNOS) in alcohol-induced gut leakiness. Methods The permeability of the Caco-2 monolayer was assessed by transepithelial electrical resistance and flux of fluorescein sulfonic acid. miR-212 was measured by real-time polymerase chain reaction. The wild-type, iNOS knockout, and miR-212 knockdown mice were fed with alcohol diet (29% of total calories, 4.5% v/v) for 8 weeks. The LNA-anti-miR-212 was used to inhibit miR-212 expression in mice. The alcohol-induced intestinal permeability, miR-212 expression, and liver injuries in mice were measured. Results Our in vitro monolayer and in vivo mice studies showed that: (i) alcohol-induced overexpression of the intestinal miR-212 and intestinal hyperpermeability is prevented using miR-212 knockdown techniques; and (ii) iNOS is up-regulated in the intestine by alcohol and that iNOS signaling is required for alcohol-induced miR-212 overexpression, ZO-1 disruption, gut leakiness, and steatohepatitis. Conclusions These studies thus support a novel miR-212 mechanism for alcohol-induced gut leakiness and a potential target that could be exploited for therapeutic intervention to prevent leaky gut and liver injury in alcoholics.

The measurement of lecithin: cholesterol acyltransferase (LCAT, EC 2.3.1.43) activity is important in high-density lipoprotein (HDL) metabolism study and cardiovascular disease (CVD) risk assessment. However, current methods suffer from complex design and preparation of exogenous substrate, low reproducibility, and interference of cofactors. In this study, we developed a simple and precise high performance liquid chromatography (HPLC) method for the measurement of LCAT activity. By using 7-dehydrocholesterol (7-DHC) and 1,2-didecanoyl-sn-glycero-3-phosphocholine(10:0PC) as substrates, and an LCAT activating peptide (P642) as activator and emulsifier, the substrate reagent was easily made by vortex. The substrate reagent was mixed with serum samples (50:1, v/v) and incubated at 37 °C for 1 h. After incubation, the lipid was extracted with hexane and ethanol. With a conjugated double bond and ultraviolet absorption, 7-DHC and its esterification product could be separated and analyzed by a single HPLC run without calibration. LCAT activity was a linear function of the serum sample volume and the intra- and total assay coefficients of variation (CV) less than 2.5% were obtained under the standardized conditions. The substrate reagent was stable, and assay result accurately reflected LCAT activity. LCAT activities in 120 healthy subjects were positively correlated with triglyceride (P

Recent studies have found that carnitine and acylcarnitines (AcyCNs) are potential biomarkers for many metabolic diseases, including inherited disorders, diabetes and coronary atherosclerotic artery disease (CAD). Here we presented and validated a method for measurement of free carnitine and twelve AcyCNs in human serum by using electrospray ionization tandem mass spectrometry (ESI-MS/MS). Serum samples were mixed with isotopic labeled internal standards and extracted with isopropanol. Carnitine and AcyCNs were separated within 5min by isocratic elution on a hydrophilic interaction liquid chromatographic column (HILIC) and detected with electrospray ionization (ESI) in positive ion mode with multiple reaction monitor (MRM) mode. This method was linear in response with correlation coefficients higher than 0.999. Analytical recoveries were 89.4%–105.4% with an average of 98.7%. The intra-run and total imprecisions were 0.9–4.7% and 1.5–14.1%, respectively. Stability tests showed that all the compounds were stable in serum for at least 6 month at −80 °C, but unstable when stored at room temperature (RM) and 4 °C.Serum carnitine and AcyCNs concentrations of 472 apparently healthy subjects were analyzed. Significant associations between the metabolites and traditional CAD risk factors were observed. The established HILIC–ESI-MS/MS method was simple, precise, and sensitive and may be used as an efficient tool in CAD risk assessment and research.

We have shown that alcohol increases Caco-2 intestinal epithelial cell monolayer permeability in vitro by inducing the expression of redox-sensitive circadian clock proteins CLOCK and PER2 and that these proteins are necessary for alcohol-induced hyperpermeability. We hypothesized that alcohol metabolism by intestinal Cytochrome P450 isoform 2E1 (CYP2E1) could alter circadian gene expression ( Clock and Per2), resulting in alcohol-induced hyperpermeability. In vitro Caco-2 intestinal epithelial cells were exposed to alcohol, and CYP2E1 protein, activity, and mRNA were measured. CYP2E1 expression was knocked down via siRNA and alcohol-induced hyperpermeability, and CLOCK and PER2 protein expression were measured. Caco-2 cells were also treated with alcohol or H2O2 with or without N-acetylcysteine (NAC) anti-oxidant, and CLOCK and PER2 proteins were measured at 4 or 2 h. In vivo Cyp2e1 protein and mRNA were also measured in colon tissue from alcohol-fed mice. Alcohol increased CYP2E1 protein by 93% and enzyme activity by 69% in intestinal cells in vitro. Alcohol feeding also increased mouse colonic Cyp2e1 protein by 73%. mRNA levels of Cyp2e1 were not changed by alcohol in vitro or in mouse intestine. siRNA knockdown of CYP2E1 in Caco-2 cells prevented alcohol-induced hyperpermeability and induction of CLOCK and PER2 proteins. Alcohol-induced and H2O2-induced increases in intestinal cell CLOCK and PER2 were significantly inhibited by treatment with NAC. We concluded that our data support a novel role for intestinal CYP2E1 in alcohol-induced intestinal hyperpermeability via a mechanism involving CYP2E1-dependent induction of oxidative stress and upregulation of circadian clock proteins CLOCK and PER2.

The impact of Roux-en-Y gastric bypass (RYGB) on weight loss and co-morbid disease resolution is well established. However, the mechanisms underlying the procedure remain incompletely understood. Intestinal remodeling involving glucose transporters (GLUTs) may play a crucial role. Rat studies have demonstrated morphological adaptation of GLUTs within adipose and intestinal cells in association with the reprogramming of glucose metabolism. There is a limited understanding of the variations in expression amongst GLUT family receptors in the human intestine. The aim of this study was to evaluate and describe jejunal GLUT expression patterns in the obese versus non-obese. Tissue samples were collected from 19 adults (age ≥18) patients with morbid obesity undergoing elective RYGB. Specimens were obtained from excess jejunum removed during the stapled jejuno-jejunal anastomosis. All subjects met National Institutes of Health criteria for bariatric surgery (body mass index or BMI ≥40 or ≥35 with obesity-related comorbidities). Exclusion criteria included age less than 18, age greater than 65, patients undergoing a revision procedure, and the presence of a seizure disorder (possible association with GLUT-1 deficiency syndrome). Five samples were obtained from non-obese subjects (average BMI 26.7) without diabetes who were consenting organ donors after brain death. Samples of jejunum from non-obese individuals were obtained at the time of organ procurement. Institutional Review Board and Gift of Hope approval was obtained. Specimens underwent quantitative real-time PCR and Western blotting. Western blot densitometry was performed using Image J software. Student T test was performed using SPSS statistics software. GLUT-1 and GLUT-7 expression were not detected in the jejunum of either group. No difference in expression pattern was observed for GLUT-2, GLUT-4, and GLUT-9 between the groups. Western blot band density of GLUT-5 to loading control (GADPH) mean ratio was 0.21 (SD = 0.20) in obese specimens compared to 0.56 (SD = 0.17) in non-obese. Densitometry revealed GLUT-5 levels in the jejunum of the obese were significantly lower than non-obese specimens (P

Diarrhea is one of the common symptoms that significantly affects quality of life in patients with inflammatory bowel disease (IBD). The clinical manifestation of diarrhea is mainly dependant on the type of IBD and the location, extent and severity of intestinal inflammation. Understanding the pathophysiologic mechanisms of diarrhea in patients with IBD will be beneficial to developing effective treatments for IBD-associated diarrhea. In recent years, modern molecular techniques have been used intensively to dissect the role of the intestinal microbiota, epithelial barrier and the host immune system in the mechanisms of IBD-induced diarrhea. These studies have significantly advanced our knowledge of the mechanisms of IBD-induced diarrhea. In this article, we focus on the new and critical molecular insights into the contributions of the intestinal microbiota, epithelial tight junctions, proinflammatory cytokines and microRNA as potential mechanisms underlying to IBD-induced diarrhea.

Background Several studies have indicated that endotoxemia is the required co-factor for alcoholic steatohepatitis (ASH) that is seen in only about 30% of alcoholics. Recent studies have shown that gut leakiness that occurs in a subset of alcoholics is the primary cause of endotoxemia in ASH. The reasons for this differential susceptibility are not known. Since disruption of circadian rhythms occurs in some alcoholics and circadian genes control the expression of several genes that are involved in regulation of intestinal permeability, we hypothesized that alcohol induces intestinal hyperpermeability by stimulating expression of circadian clock gene proteins in the intestinal epithelial cells.

Alcohol consumption is associated with the risk of progressive cancers including colon and breast cancer. The mechanisms for the alcohol-induced aggressive behavior of these epithelial cancer cells have not been fully identified. Epithelial-mesenchymal transition (EMT) is a developmental program recently shown to play a role in cancer progression and metastases. We hypothesized that alcohol might promote cancer progression by inducing EMT in cancer cells and tested this hypothesis by assessing alcohol-stimulated changes in phenotypic markers of EMT as well as the EMT transcription factor Snail and its related cell signaling.Colon and breast cancer cell lines and a normal intestinal epithelial cell line were tested as well as colonic mucosal biopsy samples from alcoholic subjects. Cells were treated with alcohol and assessed for EMT-related changes using immunofluorescent microscopy, western blotting, reporter assays, RT-PCR, and knockdown of Snail with siRNA.We show alcohol upregulated the signature EMT phenotypic marker vimentin as well as matrix metalloprotease (MMP)-2, MMP-7, and MMP-9 and cell migration in colon and breast cancer cells-all characteristics of EMT. Alcohol also stimulated nuclear localization of Snail phosphorylated at Ser246, transcription from a Snail reporter plasmid, and Snail mRNA expression by RT-PCR. Snail siRNA knockdown prevented alcohol-stimulated vimentin expression. In vivo, Snail expression was significantly elevated in colonic mucosal biopsies from alcoholics. Also, we found alcohol stimulated activation of epidermal growth factor receptor (EGFR) signaling and an EGFR inhibitor blocked alcohol-induced cell migration and Snail mRNA expression.Collectively, our data support a novel mechanism for alcohol promoting cancer progression through stimulating the EMT program in cancer cells via an EGFR-Snail mediated pathway. This study reveals new pathways for alcohol-mediated promotion of cancer that could be targeted for therapy or prevention of alcohol-related cancers.

Alcoholic liver disease (ALD) requires endotoxemia and is commonly associated with intestinal barrier leakiness. Using monolayers of intestinal epithelial cells as an in vitro barrier model, we showed that ethanol-induced intestinal barrier disruption is mediated by inducible nitric oxide synthase (iNOS) upregulation, nitric oxide (NO) overproduction, and oxidation/nitration of cytoskeletal proteins. We hypothesized that iNOS inhibitors [NG-nitro-l-arginine methyl ester (l-NAME), l-N(6)-(1-iminoethyl)-lysine (l-NIL)] in vivo will inhibit the above cascade and liver injury in an animal model of alcoholic steatohepatitis (ASH).Male Sprague-Dawley rats were gavaged daily with alcohol (6 g/kg/d) or dextrose for 10 weeks +/- l-NAME, l-NIL, or vehicle. Systemic and intestinal NO levels were measured by nitrites and nitrates in urine and tissue samples, oxidative damage to the intestinal mucosa by protein carbonyl and nitrotyrosine, intestinal permeability by urinary sugar tests, and liver injury by histological inflammation scores, liver fat, and myeloperoxidase activity.Alcohol caused tissue oxidation, gut leakiness, endotoxemia, and ASH. l-NIL and l-NAME, but not the d-enantiomers, attenuated all steps in the alcohol-induced cascade including NO overproduction, oxidative tissue damage, gut leakiness, endotoxemia, hepatic inflammation, and liver injury.The mechanism we reported for alcohol-induced intestinal barrier disruption in vitro - NO overproduction, oxidative tissue damage, leaky gut, endotoxemia, and liver injury - appears to be relevant in vivo in an animal model of alcohol-induced liver injury. That iNOS inhibitors attenuated all steps of this cascade suggests that prevention of this cascade in alcoholics will protect the liver against the injurious effects of chronic alcohol and that iNOS may be a useful target for prevention of ALD.

Because only 30% of alcoholics develop alcoholic liver disease (ALD), a factor other than heavy alcohol consumption must be involved in the development of alcohol-induced liver injury. Animal and human studies suggest that bacterial products, such as endotoxins, are the second key co-factors, and oxidant-mediated gut leakiness is one of the sources of endotoxemia. Probiotics have been used to prevent and treat diseases associated with gut-derived bacterial products and disorders associated with gut leakiness. Indeed, "probiotic"Lactobacillus rhamnosus has been successfully used to treat alcohol-induced liver injury in rats. However, the mechanism of action involved in the potential beneficial effects of L. rhamnosus in alcohol liver injury is not known. We hypothesized that probiotics could preserve normal barrier function in an animal model of ALD by preventing alcohol-induced oxidative stress and thus prevent the development of hyperpermeability and subsequent alcoholic steatohepatitis (ASH). Male Sprague-Dawley rats were gavaged with alcohol twice daily (8 gm/kg) for 10 weeks. In addition, alcoholic rats were also treated with once daily gavage of either 2.5 x 10(7) live L. rhamnosus Gorbach-Goldin (LGG) or vehicle (V). Intestinal permeability (baseline and at 10 weeks) was determined using a sugar bolus and GC analysis of urinary sugars. Intestinal and liver tissues were analyzed for markers of oxidative stress and inflammation. In addition, livers were assessed histologically for severity of ASH and total fat (steatosis). Alcohol+LGG (ALC+LGG)-fed rats had significantly (P< or =.05) less severe ASH than ALC+V-fed rats. L. rhamnosus Gorbach-Goldin also reduced alcohol-induced gut leakiness and significantly blunted alcohol-induced oxidative stress and inflammation in both intestine and the liver. L. rhamnosus Gorbach-Goldin probiotic gavage significantly ameliorated ASH in rats. This improvement was associated with reduced markers of intestinal and liver oxidative stress and inflammation and preserved gut barrier function. Our study provides a scientific rationale to test probiotics for treatment and/or prevention of alcoholic liver disease in man.

Background and Aims: Alcohol-induced gut leakiness is a key factor in alcoholic liver disease (ALD); it allows endotoxin to enter the circulation and initiate liver damage. Zonula occludens 1 (ZO-1) protein is a major component of tight junctions that regulates intestinal permeability. microRNAs (miRNAs) are recently discovered regulatory molecules that inhibit expression of their target genes. The aims of our study were: (i) to investigate the effect of alcohol on miRNA-212 (miR-212) and on expression of its predicted target gene, ZO-1, (ii) to study the potential role of miR-212 in the pathophysiology of ALD in man. Methods: Using a TaqMan miRNA assay system, we measured miR-212 expression levels in colon biopsy samples from patients with ALD and in Caco-2 cells (a human intestinal epithelial cell line) treated with or without EtOH. We measured ZO-1 protein levels using western blots. ZO-1 mRNA was assayed using real-time PCR. Intestinal barrier integrity was measured using fluorescein sulfonic acid clearance and immunofluorescent staining for ZO-1. Results: Ethanol increased miR-212 expression, decreased ZO-1 protein levels, disrupted tight junctions, and increased the permeability of monolayers of Caco-2 cells. An miR-212 over-expression is correlated with hyperpermeability of the monolayer barrier. miR-212 levels were higher in colon biopsy samples in patients with ALD than in healthy controls; ZO-1 protein levels were lower. Conclusion: These data suggest a novel mechanism for alcohol-induced gut leakiness, one in which EtOH induces miR-212 over-expression which causes gut leakiness by down-regulating ZO-1 translation. This mechanism is a potential therapeutic target for leaky gut in patients with or at risk for ALD.

Background: Colitis in interleukin (IL)-10−/− mice is a CD4+ T helper 1 (TH1)-mediated disease characterized by intermittent, transmural inflammation reminiscent of human Crohn's disease. In this study, we investigated the hypothesis that production of the CXC chemokine CXCL10 (interferon [IFN]γ-inducible protein 10) enhances induction of inflammatory responses in draining lymph nodes (LNs) and promotes colonic TH1 cell recruitment. Methods: Colitis was induced in B6 IL-10−/− mice. Mice were given anti-CXCL10 mAb in 2-week intervals before and after peak colitis. Colitis severity was graded and cytokine/chemokine levels were analyzed by real-time polymerase chain reaction. Cell yields were quantitated and effector cell recruitment was assessed by recovery of transferred D011.10 TH1 cells shortly (72 h) after transfer. Results: Treatment with anti-CXCL10 during colitis development decreased clinical and histologic disease severity as well as cytokine/chemokine mRNA and accumulation of mononuclear cells in LNs and colon. Treatment of mice with severe colitis reduced colitis scores and cell yields to lesser degrees. Anti-CXCL10 specifically decreased recruitment of transferred TH1 cells into mesenteric LNs (MLNs) and colon of IL-10−/− mice by 75% (P < 0.05). Conclusion: These results suggest that CXCL10 plays a dual role in colitis development by enhancing TH1 cell generation in inductive sites and promoting effector cell recruitment to inflamed tissue. Blockade of CXCL10 may be a useful adjunct to remission-inducing therapies in inflammatory bowel disease (IBD) by impairing disease recurrence through selective inhibition of effector cell generation and trafficking in vivo.

TNF-alpha is an important pro-inflammatory mediator that influences host defense against infection and cancer. Previous examinations of TNF-alpha release and synthesis within the context of age have provided conflicting data, as both increased and decreased TNF-alpha synthesis have been described in aged populations. The present study was designed to reevaluate TNF-alpha production and synthesis in primary cultured peritoneal macrophages of young and 18-month-old rats. We were also interested in the link between the production of this cytokine and other important mediators, such as prostaglandin I(2) (PGI(2)) and nitric oxide (NO) in these rats. Primary cultured peritoneal macrophages of rat were stimulated with 1.0 microg/ml of lipopolysaccharide (LPS) for 12 h. The level of TNF-alpha protein in culture supernatant was measured by enzyme-linked-immunosorbent-assay (ELISA), and TNF-alpha mRNA production was assessed by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). At the same time, the levels of NO and PGI(2) were measured. Macrophages from 18-month-old rats produced more TNF-alpha protein, PGI(2) and TNF-alpha mRNA than those from the young rats (2 month). There was no difference in NO production of macrophages between 18-month-old and young rats. The results demonstrate that TNF-alpha and PGI(2) production by rat macrophages increase with age. The results also suggest that NO might not contribute to the increased TNF-alpha production in 18-month-old rat macrophages.

The purpose of this study was to examine whether rCGRP has effects on TNF-alpha produced by mouse resident peritoneal macrophages. Macrophages were obtained from the peritoneal exudate of male Balb/c mouse. The cells were plated on culture dishes at a density of 2.5x10(5) cells per well and allowed to adhere for 2 hr. Pretreatment with rCGRP (10 nM-1 microM) for 24 hr, the macrophages were cultured with LPS 1 microg/ml for another 24 h. The medium was harvested for measuring TNF-alpha by ELISA kits. The results showed that rCGRP had no direct effects on TNF-alpha production, but it inhibited LPS-induced TNF-alpha production in a concentration-dependent manner. When rCGRP was at a concentration of 1 microM, the LPS-induced TNF-alpha production was inhibited by 39%. The effect of rCGRP was reversed by hCGRP(8-37) (10 microM), an antagonist of CGRP1 receptor. The LPS-induced TNF-alpha production from macrophages was also inhibited by forskolin 3 microM, an activator of adenylate cyclase. Furthermore, pretreatment with H-89 1 microM or Rp-cAMPS 100 microM, the inhibitors of cAMP-dependent protein kinase, the effect of rCGRP was abolished. These data suggest that the LPS-induced TNF-alpha production is inhibited by rCGRP via activation of cAMP responses in mouse resident peritoneal macrophages.

In the present study, the role of calcium in endotoxin-induced CGRP release was studied. 2.5-50 microg/mL endotoxin and 1-10 mmol/L caffeine caused concentration-dependent increase of CGRP release from rat spinal cord in vitro. However, no additive effect could be found when caffeine and endotoxin were concomitantly incubated. By using capsaicin, Ca(2+)-free medium, Omega-Conotoxin, nifedipine, W-7, ryanodine, MgCl(2), Tris-ATP, ruthenium red, the results indicate that the release of CGRP evoked by endotoxin from the sensory fibers of rat spinal cord is dependent on extracellular calcium. After entering into the cell through the N-type calcium channel, calcium binds to calmodulin, and triggers calcium release from intracellular calcium store by activating the caffeine-sensitive but ryan-odine-insensitive mechanism.

The weld is a typical dissimilar metal weld (DMW). As its large grain, anisotropism and narrow moving space for probe, it is difficult for practical ultrasonic testing. On the basis of studying weld structure, this thesis firstly discusses the sonic propagation path of different incident angle, and then calculates the reflectivity and transmittivity, from which the ratio-angle curve will be plotted, finally simulates & analyzes the ultrasonic testing with software CIVA. The analysis results show that proper selection of the incident angle will provide suitable incident angle range for the following experiments. With the CIVA analysis results, it will also provide references for choosing proper probe parameters and relative technics for following research.Copyright © 2013 by ASME

The circadian clock orchestrates temporal patterns of physiology and behavior relative to the environmental light:dark cycle by generating and organizing transcriptional and biochemical rhythms in cells and tissues throughout the body. Circadian clock genes have been shown to regulate the physiology and function of the gastrointestinal tract. Disruption of the intestinal epithelial barrier enables the translocation of proinflammatory bacterial products, such as endotoxin, across the intestinal wall and into systemic circulation; a process that has been linked to pathologic inflammatory states associated with metabolic, hepatic, cardiovascular and neurodegenerative diseases – many of which are commonly reported in shift workers. Here we report, for the first time, that circadian disorganization, using independent genetic and environmental strategies, increases permeability of the intestinal epithelial barrier (i.e., gut leakiness) in mice. Utilizing chronic alcohol consumption as a well-established model of induced intestinal hyperpermeability, we also found that both genetic and environmental circadian disruption promote alcohol-induced gut leakiness, endotoxemia and steatohepatitis, possibly through a mechanism involving the tight junction protein occludin. Circadian organization thus appears critical for the maintenance of intestinal barrier integrity, especially in the context of injurious agents, such as alcohol. Circadian disruption may therefore represent a previously unrecognized risk factor underlying the susceptibility to or development of alcoholic liver disease, as well as other conditions associated with intestinal hyperpermeability and an endotoxin-triggered inflammatory state.

Alcohol has been a widely used and abused substance throughout human civilization, with use reported as early as the Neolithic period circa 10,000 B.C.[1]. Alcohol remains a highly popular substance today with approximately 51 % of Americans over the age of 21 reporting alcohol use. Of these individuals, 11 % meet the criteria for alcohol abuse with approximately 18 million alcoholics in the United States. The consequences of alcohol abuse are numerous including liver cirrhosis, liver transplantation [2], and death occurring secondary to traffic accidents [3]. Thus, it is clear that chronic alcohol use/abuse is a significant public health problem.

Oxidative stress is responsible for a variety of degenerative processes in many human diseases, as either cause or effect. At present, some biomarkers of oxidative stress have been used to determine an individual’s oxidative status in relation to disease conditions. However, their accuracy, sensitivity, or specificity needs to be improved. The development of novel biomarkers for oxidative stress is urgent.

Ethanol exerts complex effects on human physiology and health. Ethanol is not only addictive, but it is also a fetal teratogen, an adult neurotoxin, and an etiologic agent in hepatic and cardiovascular disease, inflammation, bone loss, and fracture susceptibility. A large number of genes and signaling mechanisms have been implicated in ethanol's deleterious effects leading to the suggestion that ethanol is a "dirty drug." An important question is, are there cellular "master-switches" that can explain these pleiotropic effects of ethanol? MicroRNAs (miRNAs) have been recently identified as master regulators of the cellular transcriptome and proteome. miRNAs play an increasingly appreciated and crucial role in shaping the differentiation and function of tissues and organs in both health and disease. This critical review discusses new evidence showing that ethanol-sensitive miRNAs are indeed regulatory master-switches. More specifically, miRNAs control the development of tolerance, a crucial component of ethanol addiction. Other drugs of abuse also target some ethanol-sensitive miRNAs suggesting that common biochemical mechanisms underlie addiction. This review also discusses evidence that miRNAs mediate several ethanol pathologies, including disruption of neural stem cell proliferation and differentiation in the exposed fetus, gut leakiness that contributes to endotoxemia and alcoholic liver disease, and possibly also hepatocellular carcinomas and other gastrointestinal cancers. Finally, this review provides a perspective on emerging investigations into potential roles of miRNAs as mediators of ethanol's effects on inflammation and fracture healing, as well as the potential for miRNAs as diagnostic biomarkers and as targets for therapeutic interventions for alcohol-related disorders.

In inflammatory bowel disease (IBD), aberrant activation of innate and adaptive immune responses enhances mucosal permeability through mechanisms not completely understood. To examine the role of epithelial nuclear factor (NF-kappaB) in IBD-induced enhanced permeability, epithelial-specific IkappaBalpha mutant (NF-kappaB super repressor) transgenic (TG) mice were generated. NF-kB activation was inhibited in TG mice, relative to wild-type mice, following T cell-mediated immune cell activation using an anti-CD3 monoclonal antibody. Furthermore, epithelial NF-kappaB super repressor protein inhibited diarrhea and blocked changes in transepithelial resistance and transmucosal flux of alexa350 (0.35 kDa) and dextran3000 (3 kDa). In vivo perfusion loop studies in TG mice revealed reversed net water secretion and reduced lumenal flux of different molecular probes (bovine serum albumin, alexa350, and dextran3000). Cell-imaging and immunoblotting of low-density, detergent-insoluble membrane fractions confirmed that tight junction proteins (occludin, claudin-1 and zona occludens-1) are internalized through an NF-kappaB-dependent pathway. Taken together, these data suggest that IBD-associated diarrhea results from NF-kappaB-mediated tight junction protein internalization and increased paracellular permeability. Thus, reduction of epithelial NF-kappaB activation in IBD may repair defects in epithelial barrier function, reduce diarrhea, and limit protein (eg, serum albumin) losses. Epithelial NF-kappaB activation induced by mucosal T cells, therefore, actively plays a role in opening paracellular spaces to promote transmucosal fluid effux into the intestinal lumen.

We reported previously that oats supplementation prevents gut leakiness and alcoholic steatohepatitis (ASH) in our rat model of alcoholic liver disease. Because oxidative stress is implicated in the pathogenesis of both alcohol-induced gut leakiness and ASH, and because oats have antioxidant properties, we tested the hypothesis that oats protect by preventing alcohol-induced oxidative damage to the intestine. Male Sprague-Dawley rats were gavaged for 12 weeks with alcohol (starting dose of 1 g/kg increasing to 6 g/kg/day over the first 2 weeks) or dextrose, with or without oats supplementation (10 g/kg/day). Oxidative stress and injury were assessed by measuring colonic mucosal inducible nitric-oxide synthase (iNOS) (by immunohistochemistry), nitric oxide (colorimetric assay), and protein carbonylation and nitrotyrosination (immunoblotting). Colonic barrier integrity was determined by assessing the integrity of the actin cytoskeleton (immunohistochemistry) and the integrity of tight junctions (electron microscopy). Oats supplementation prevented alcohol-induced up-regulation of iNOS, nitric oxide overproduction in the colonic mucosa, and increases in protein carbonyl and nitrotyrosine levels. This protection was associated with prevention of ethanol (EtOH)-induced disorganization of the actin cytoskeleton and disruption of tight junctions. We conclude that oats supplementation attenuates EtOH-induced disruption of intestinal barrier integrity, at least in part, by inhibiting EtOH-induced increases in oxidative stress and oxidative tissue damage. This inhibition prevents alcohol-induced disruption of the cytoskeleton and tight junctions. This study suggests that oats may be a useful therapeutic agent—a nutraceutical—for the prevention of alcohol-induced oxidative stress and organ dysfunction.

Continuous disruption of circadian rhythms, as seen in human shift workers, has been associated with the development of a number of adverse mental and physiological conditions. However, scientific evidence linking circadian disruption to overall health, particularly in animal models, is not well documented. In this study, we have demonstrated that exposing C57BL/6J mice to 12-h phase shifts every 5 days for 3 mo had no effect on body weight or intestinal physiology. However, when animals were further challenged with dextran sodium sulfate to induce colitis, chronic shifting of the light-dark cycle led to a dramatic increase in the progression of the colitis as indicated by reduced body weight, abnormal intestinal histopathology, and an exacerbated inflammatory response. These data indicate that circadian disruption is an important predisposing factor that may provoke the onset or worsening of various disease states such as inflammatory disorders. This study provides further evidence for continued investigations using animal models of circadian disruption to examine the consequences of circadian disruption on health when organisms are faced with a “challenging” environment.

We recently showed that patients with inflammatory bowel disease (IBD) report significantly more sleep disturbances. To determine whether disrupted sleep can affect the severity of inflammation and the course of IBD, we used an animal model of colonic inflammation to determine the effects of acute and chronic intermittent sleep deprivation on the severity of colonic inflammation and tissue damage in colitis and recovery from this damage.Acute sleep deprivation (ASD) consisted of 24h of forced locomotor activity in a mechanical wheel rotating at a constant speed. Chronic intermittent sleep deprivation (CISD) consisted of an acute sleep deprivation episode, followed by additional sleep deprivation periods in the wheel for 6h every other day throughout the 10day study period. To induce colitis, mice were given 2% dextran sodium sulfate (DSS) in their daily drinking water for 7days. The development and severity of colitis were monitored by measuring weight loss and tissue myeloperoxidase (MPO) activity daily and colon histology scores 10days after initiation of colitis.ASD or CISD did not cause colonic inflammation in vehicle-treated mice. Changes in daily body weight, tissue MPO levels and colon histopathology score were similar between mice that were sleep deprived and controls. Daily DSS ingestion caused colitis in mice. ASD worsened colonic inflammation: tissue MPO levels in ASD/DSS-treated mice were significantly higher than in DSS-treated mice that were not sleep deprived. However, the worsening of colonic inflammation by ASD was not enough to exacerbate clinical manifestations of colitis such as weight loss. In contrast, the deleterious effects of CISD were severe enough to cause worsening of histological and clinical manifestations of colitis. The deleterious effects of sleep deprivation on severity of colitis appeared to be due to both increased colonic inflammation and a decrease in the ability of mice to recover from DSS-induced colonic injury.Both acute and chronic intermittent sleep deprivation exacerbate colonic inflammation. Thus, sleep deprivation could be an environmental trigger that predisposes IBD patients to develop flare ups and a more severe disease course. These results provide a scientific rationale to conduct an interventional trial to determine whether improvement in sleep patterns will prevent IBD flare ups, modify the disease course, and improve quality of life.

Intestinal barrier disruption has been implicated in several intestinal and systemic disorders including alcoholic liver disease (ALD). Using monolayers of intestinal (Caco-2) cells, we showed that ethanol (EtOH) disrupts the barrier integrity via destabilization of the cytoskeleton. Because proinflammatory conditions are associated with activation of NF-kappa B (NF-kappaB), we hypothesized that EtOH induces disruption of cytoskeletal assembly and barrier integrity by activating NF-kappaB. Parental cells were pretreated with pharmacological modulators of NF-kappaB. Other cells were stably transfected with a dominant negative mutant for the NF-kappaB inhibitor, I-kappaBalpha. Monolayers of each cell type were exposed to EtOH and we then monitored monolayer barrier integrity (permeability); cytoskeletal stability and molecular dynamics (confocal microscopy and immunoblotting); intracellular levels of the I-kappaBalpha (immunoblotting); subcellular distribution and activity of NF-kappaB (immunoblotting and sensitive ELISA); and intracellular alterations in the 43kDa protein of the actin cytoskeleton, polymerized F-actin, and monomeric G-actin (SDS-PAGE fractionation). EtOH caused destabilizing alterations, including I-kappaBalpha degradation, NF-kappaB nuclear translocation, NF-kappaB subunit (p50 and p65) activation, actin disassembly (upward arrow G-, downward arrow F-), actin cytoskeleton instability, and barrier disruption. Inhibitors of NF-kappaB and stabilizers of I-kappaBalpha (e.g., MG-132, lactacystin, etc) prevented NF-kappaB activation while protecting against EtOH-induced injury. In transfected I-kappaBalpha mutant clones, stabilization of I-kappaBalpha to inactivate NF-kappaB protected against all measures of EtOH-induced injury. Our data support several novel mechanisms where NF-kappaB can affect the molecular dynamics of the F-actin cytoskeleton and intestinal barrier integrity under conditions of EtOH injury. (1) EtOH induces disruption of the F-actin cytoskeleton and of intestinal barrier integrity, in part, through I-kappaBalpha degradation and NF-kappaB activation; (2) The mechanism underlying this pathophysiological effect of the NF-kappaB appears to involve instability of the assembly of the subunit components of actin network.

Crop and weed identification is very importance in precision farming field. As spectroscopy can reflects the contents of object tested, so it is possible to identify crop and weed with high correct rate. ASD FieldSpec recorded the spectrum of crops and weeds. Its waveband is 325-1075nm and with resolution of 3.5nm. One crop seedling and three kinds of weeds living together were tested. Each species has at least 30 sampling spectrum taken down. As one sample spectrum has too much data, wavelet transform reduced the data volume firstly, which compressed source signals to tens of floating numbers from 751 floating numbers. Totally 160 samples were used to build a radial basis function neural network, the object output was a 4 by 1 dimension vector. Those left 43 samples used to check the identifying capability. As neural network model has huge power in solving these pattern recognition problems. It can approach to giving finite function at any approximation. Nearly all these predicting samples classified right. Therefore, by using spectroscopy in the identification is possible, and having high correct rate. Further more, the computation is very fast. Whereas the spectrometer is expensive and easily affected by shaking and variation of light shine, it cannot installed directly on vehicles at present time. In the future, it may be possible to recognize crop and weed in real time by using spectroscopy.

Disruption of the intestinal epithelial barrier occurs in many intestinal diseases, but neither the mechanisms nor the contribution of barrier dysfunction to disease pathogenesis have been defined. We utilized a murine model of T cell-mediated acute diarrhea to investigate the role of the epithelial barrier in diarrheal disease. We show that epithelial barrier dysfunction is required for the development of diarrhea. This diarrhea is characterized by reversal of net water flux, from absorption to secretion; increased leak of serum protein into the intestinal lumen; and altered tight junction structure. Phosphorylation of epithelial myosin II regulatory light chain (MLC), which has been correlated with tight junction regulation in vitro, increased abruptly after T cell activation and coincided with the development of diarrhea. Genetic knockout of long myosin light chain kinase (MLCK) or treatment of wild-type mice with a highly specific peptide MLCK inhibitor prevented epithelial MLC phosphorylation, tight junction disruption, protein leak, and diarrhea following T cell activation. These data show that epithelial MLCK is essential for intestinal barrier dysfunction and that this barrier dysfunction is critical to pathogenesis of diarrheal disease. The data also indicate that inhibition of epithelial MLCK may be an effective non-immunosuppressive therapy for treatment of immune-mediated intestinal disease.

Background & Aims: Chemokines mediate cell trafficking in inflammatory states such as allograft rejection. However, their role in small-bowel allograft rejection has not been defined. The aim of this study was to examine the roles of type 1 helper T-cell chemokines in small-bowel allograft rejection. Methods: Mucosal histology, chemokine messenger RNA (real-time polymerase chain reaction), and cell isolates were examined in small-bowel allografts and isografts. Interferon-γ-inducible protein-10/ CXC chemokine receptor (CXCR) 3 interactions were specifically evaluated by using allografts from interferon-γ-inducible protein-10 −/− donors and adoptive transfer of CXCR3 −/− T cells into recombination activating gene (RAG)-1 −/− recipients of small-bowel allografts. Results: Type 1 helper T-cell cytokine (interferon-γ) and chemokine (interferon-γ-inducible protein-10, monokine induced by interferon-γ, macrophage-inflammatory protein-1α, and regulated on activation, normal T cells expressed and secreted) messenger RNA up-regulation was detected (real-time polymerase chain reaction) by postoperative day 3 in small-bowel allografts. Interferon-γ-inducible protein-10 +/+ small-bowel allograft rejection was associated with a dramatic (>7-fold) increase in CXCR3 + host T cells in the graft lamina propria. With interferon-γ-inducible protein-10 −/− small-bowel allografts, CXCR3 + host T-cell infiltration of the graft lamina propria was markedly decreased and rejection was significantly delayed. Whereas adoptive transfer of wild-type B6 (CXCR3 +/+ ) T cells into B6 (RAG-1 −/− ) recipients induced rapid rejection of CB6F1 small-bowel allografts, rejection was significantly delayed (29.2 ± 8.7 days vs. 16.5 ± 3.1 days; P −/− ) mice reconstituted with T cells from B6 (CXCR3 −/− ) mice. Conclusions: Recruitment of CXCR3 + host T cells by donor derived interferon-γ-inducible protein-10 may precipitate small-bowel allograft rejection. These data highlight the importance of type 1 helper T cell-related chemokines in promoting cell-mediated rejection responses in small-bowel allografts and suggest that interferon-γ-inducible protein-10 is an attractive therapeutic target for humanized monoclonal antibody strategies.

In the present study, we investigated the changes in capsaicin- and endotoxin-induced calcitonin gene-related peptide (CGRP) release from mesenteric arterial bed (MAB) and spinal cord slices (SCS) in 2-month-old and 18-month-old Wistar rats. The isolated MAB or SCS was perfused or incubated in vitro. The CGRP-like immunoreactivity in perfusate or supernatant was measured by radioimmunoassay. The results showed that endotoxin triggered CGRP release from isolated rat MAB and SCS, which represent the peripheral and central terminals of CGRP-containing sensory nerves, respectively. Either basal or stimulated CGRP release induced by capsaicin and endotoxin was significantly decreased as the rats aged from 2 to 18 months. The basal CGRP release was 14.9 +/- 1.8 and 5.8 +/- 1.0 pg/ml from MAB and 3.50 +/- 0.54 and 1.78 +/- 0.16 pg/ml/mg from SCS in 2-month-old and 18-month-old rats, respectively. The release of CGRP evoked by capsaicin (10(-7) mol/L) and endotoxin (1 to approximately 5 microg/ml) from MAB and SCS was significantly decreased by more than 50% in 18-month-old rats. These data suggest that both the basal and capsaicin- or endotoxin-stimulated CGRP release from MAB and SCS display a significant decrement in aged rats that may have some physiological, pathological, and behavioural relevance in age-related diseases.

The secretion of IL-6 after stimulation of macrophages has been found to play a central role in the regulation of defense mechanism, haematopoiesis, and acute phase reaction. It was reported that cAMP is involved in the regulation of IL-6 production. Since calcitonin gene-related peptide (CGRP) is known to increase cAMP accumulation in mouse macrophages, we examined whether CGRP would induce IL-6 release in macrophages. Macrophages were obtained from the peritoneal exudate of male Balb/c mouse. The cells were plated on culture dishes at a density of 2.5 x 10(5) cells per well and allowed to adhere for 2 h. After incubation for 48 h with two changes of PRMI-1640, the macrophages were cultured with CGRP and LPS 1 microg/ml for 12 h. The IL-6 level in medium was measured by ELISA kits. The results showed that CGRP had no direct effects on IL-6 production, but it potentiated LPS-induced IL-6 production in a concentration-dependent manner. When CGRP was at a concentration of 10(-10) M, the LPS-induced IL-6 production was increased from 5.16 +/- 0.48 to 8.88 +/- 0.48 ng/ml. The effect of CGRP 10(-10) M was reversed by hCGRP(8-37) 10(-8) M, an antagonist of CGRP1 receptor. The LPS-induced IL-6 production from macrophages was also potentiated by forskolin 5 microM, an activator of adenylate cyclase. Furthermore, pretreatment with H-89 1 microM or Rp-cAMPS 100 microM, the inhibitors of cAMP-dependent protein kinase, inhibited the effect of CGRP by 31% and 98%, respectively. These results demonstrate that the LPS-induced IL-6 release is potentiated by CGRP via the activation of cAMP pathway in mouse resident peritoneal macrophages.